Photonics, with its virtually infinite bandwidth, electrical noise immunity, small size, low cost, and increased capacity are inserted into a number of military platforms to handle higher data rates and larger traffic volumes. Such increased data rates between the various subsystems drive the interconnect solution to be fiber optics.
These military fiber optic cables are meant for severe environments, with shock, vibration, and wide temperature ranges not typically required for commercial applications.
Currently, the manufacturing of these aircraft fiber optic cables is manually intensive, requiring a high degree of manual dexterity and skill to achieve stringent performance requirements.
The Fiber Optic Interconnect Technology (FOIT) program began in 2001 as a Navy ManTech effort at fiber optic cable assembly automation.
The FOIT, a phased development program, was incrementally funded to:
- Help improve cable performance and reliability.
- Reduce life cycle cost for fiber optic insertion into military applications.
- Develop and demonstrate key technologies to retire technology. insertion risks for automating the cable assembly process.
Fiber optic cables, utilizing the MIL-T-29504/4 and /5 connectors with ceramic ferrules, PC polish and Lucent Flightguide Cable that are used in production of F-16 and F-22 optical interconnect harnesses, were selected as the baseline cable for this project.
This cable poses a number of challenges for automation. Process steps for military and commercial cable assembly manufacturing were systematically identified, partitioned, and optimize within an automated process flow.
Five process islands were designed and fabricated at kSARIA using systems engineering assistance from Lockheed-Martin.
Figure 1 shows five island work cell/stations under the FOIT program for automated assembly of fiber optic cables, which breaks up the assembly process into five different automation islands:
- Cable Preparation: Where the raw materials are cut to length, spooled and placed into a material handling pallet for further processing.
- Connector Assembly: The cable is stripped > Kevlar strength member cut > buffer is stripped > fiber is cleaned > fiber is cleaved > and termini is attached to the fiber.
- Cure Island: Cures the pallet loaded cables to a user selected cure profile.
- End Face Polishing System: The ends of the cables are automatically polished.
- Inspection & Test Cable: Extensive performance verification, optimization and validation of each of the FOIT work cells.
One of the challenges for implementing the FOIT developed technology into production of military fiber optic cables is qualification of the system and processes for flight programs. Proof is required that the new automated process meets or exceeds the performance requirements, and this "Proof" must be approved by the individual program systems engineering prior to insertion into production.